CVE-2009-2055
KEVCisco IOS XR Border Gateway Protocol (BGP) Denial-of-Service Vulnerability
Description
Cisco IOS XR,when BGP is the configured routing feature, allows remote attackers to cause a denial-of-service (DoS).
Cisco IOS XR 3.4.0 through 3.8.1 allows remote attackers to cause a denial of service (session reset) via a BGP UPDATE message with an invalid attribute, as demonstrated in the wild on 17 August 2009.
CVSS 3.1 vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:HPublishedAug 19, 2009
Last modifiedJun 16, 2026
Added to KEVMar 25, 2022
Remediation dueApr 15, 2022
References
- mailman.nanog.org/pipermail/nanog/2009-August/012719.htmlMailing List
- securitytracker.com/id?1022739Broken Link
- cisco.com/en/US/products/products_security_advisory09186a0080af150f.shtmlPatchVendor Advisory
- cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2009-2055US Government Resource
0 recent articles mention this CVE
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Risk assessment · High
Actively exploited. Patch immediately.
- Exploitation
- Confirmed in the wild (CISA KEV)
- Federal remediation deadline
- Overdue by 1655 days
- CVSS
- 5.9 MEDIUM
- EPSS (30-day exploit probability)
- 3.3% · top 12% of all CVEs
- Weakness
- CWE-20
- Attack vector
- Network, remotely reachable
- Preconditions
- No privileges and no user interaction
Recommended actions
- 1.Apply updates per vendor instructions.
- 2.Treat as emergency change: patch or isolate internet-facing instances first.
- 3.Review exposure: confirm which instances are reachable from the internet and restrict access until patched.
- 4.Hunt for compromise: review logs for the disclosure window, not just from the patch date.
Assessment is derived automatically from the live signals above; verify against your own asset inventory.